Question

A researcher wishes to examine the relationship between years of schooling completed and the number of pregnancies in young women. Her research discovers a linear relationship, and the least squares line is: ˆ y = 2 − 4 x where x is the number of years of schooling completed and y is the number of pregnancies. The slope of the regression line can be interpreted in the following way:When amount of schooling increases by one year, the number of pregnancies increases by 2.When amount of schooling increases by one year, the number of pregnancies increases by 4.When amount of schooling increases by one year, the number of pregnancies decreases by 2.When amount of schooling increases by one year, the number of pregnancies decreases by 4

Answer 1

The slope of the regression line is -4. This means that for every one unit increase in the number of years of schooling completed (x), the predicted number of pregnancies (y) decreases by 4.

Therefore, the correct interpretation of the slope is:

"When the amount of schooling increases by one year, the number of pregnancies decreases by 4."